Arsenal scored three second-half goals to beat Cologne, while Everton lost 0-3 to atalanta and a resurgent AC Milan picked up a 5-1 victory away over Austria Vienna in the Europa League group stage matches.
Goals from Sead Kolasinac, Alexis Sanchez and Hector Bellerin canceled out Jhon Cordoba's long-range opener as Arsenal on Thursday came from behind to beat Cologne at the Emirates Stadium in London, reports Efe.
The game began an hour late due to crowd trouble outside the stadium involving thousands of ticketless visiting supporters, with some fans also clashing with stewards inside the ground.
Arsenal started sluggishly, and Cologne took the lead with a spectacular 40-yard Cordoba strike over the stranded David Ospina.
"I felt that we were playing too deep, all of us, and didn't put enough pressure on them," Arsenal coach Arsene Wenger told his club's website as he analysed his team's poor start.
After being booed off by the home crowd at half-time, Arsenal equalised through substitute Kolasinac's volley, then took the lead through a stunning curler from Sanchez.
Bellerin added a third after goalkeeper Timo Horn spilled Theo Walcott's shot.
In Vienna, new recruit Andre Silva slammed a hat-trick, while a goal each from Hakan Calhanoglu and Suso led a new-look AC Milan, who invested heavily over the summer, to a 5-1 victory.
Everton, who lost their previous two English Premier League (EPL) games, continued their poor form, losing 0-3 to Atalanta in Bergamo. Andrea Masiello (27th minute), Alejandro Gomez (41st) and Bryan Cristante (44th) scored for the Italian club.
"Everyone can do their maximum to gain a result. But it is not the time or the place to criticise the players. I have to criticise myself because the team was not prepared for this tonight," Everton coach Ronald Koeman was quoted as saying by his club's website.
"What I saw was a big difference in belief and confidence between Atalanta and Everton.
They had aggression and passion. Atalanta showed to us the passion that you have to have when you play football."
Hosts Red Star Belgrade and Bate Borisov drew 1-1 in Group H's other game. Red Star's Nemanja Radonjic scored in the 54th minute, while Nikolai Signevich scored the equaliser.
Meanwhile, Braga came from behind to beat hosts Hoffenheim 2-1 in Europa League's Group C while Hertha Berlin shared the spoils with Athletic Bilbao following a goalless draw at the San Mames Stadium in Bilbao, reports Xinhua news agency.
European debutants Hoffenheim were unable to defend Sandro Wagner's opener as goals from Joao Teixeira and Dyego Sousa allowed Braga to snatch a 2-1 comeback victory on the road.
Lazio defeated Vitesse 3-2 away, thanks to second-half goals from Marco Parolo, Ciro Immobile and Alessandro Murgia.
Villarreal to get the better of Astana 3-1 at home. Marseille rode on Adil Rami's 48th-minute strike to beat Konyaspor 1-0.
OGC Nice overwhlemed Zulte Waregem 5-1 away.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)